Reclosable Pouring Element for Composite Cardboard/Plastic Packaging

ABSTRACT

A re-closable pouring element for cardboard/plastic composite packages, especially for drinks packages, which comprises an encompassing fixing flange as well as a frame element that is provided with an outer thread and an inner thread, a cutting element that has an outer thread, and a screw cap having an inner thread, wherein the cutting element is produced in the spraying position at the end of the frame element opposite to the fixing flange and together with this has been injection moulded across at least one connecting bridge in a unitary manner, and wherein the cutting element is situated in the interior of the frame element at the assembly position of the pouring element.

The invention relates to a re-closable pouring element for cardboard/plastic composite packages, especially for drinks packages, which comprises an encompassing sealing flange as well as a frame element that is provided with an outer thread, a cutting element that has both an outer thread and an inner thread, and a screw cap having an inner thread, wherein the cutting element is produced in the spraying position at the end of the frame element opposite to the fixing flange and together with has been injection moulded across at least one connecting bridge in a unitary manner, and wherein the cutting element is situated in the interior of the frame element at the assembly position of the pouring element.

Many types of re-closable pouring elements for throw-away packages have been known for a long time. Such types having screw caps are especially liked since they provide a reliably tight re-sealing facility, so that the re-sealed package can be shaken without the contents escaping.

This type of pouring element is frequently constructed in three parts, wherein one part is a frame element that is provided with an encircling flange that is firmly fixed to the upper side of the composite package. By operating together with the screw cap, the actual shape of the frame becomes cylinder-shaped, a cutting element being arranged inside this cylinder, that is operated by the screw cap so that it has the function of opening the composite package for which purpose, on opening the screw cap to the frame element for the first time, it is moved over the interior of the package so that a pour-opening is provided below the pouring element.

The pouring element referred to initially and described above is known from the patent WO 02/28728 A1. Because of the firm attachment between the frame element and the cutting element across connecting bridges in this known pouring element, with this known pouring element, the assembly of the frame and cutting elements connected together only needs to be provided with the screw cap.

Another three-component pouring element has been described in the patent EP 1 088 764 B1. Here also, the frame element is provided with an outer thread and the screw cap is provided with a corresponding inner thread. Here again, the cutting element, during the first operation of the screw cap across the corresponding thread on the inside of the frame element and on the outer circumference of the cutting element, is forced to penetrate axially into the package material. There, the frame element and cutting element are connected together at the same time during the construction, by injection moulding, although the cutting element is attached at the flange-end to the frame component. During the assembly, the cutting element and screw cap must be introduced from opposite sides by way of opposing movements onto or into the frame element.

Furthermore, a three-component pouring element is known from the patent WO 2004/000667, although in this case the opening component is not operated by a screwing system. The actual opening procedure, in this case, takes place rather by a combination of a piercing movement with a turning movement, in other words through the sequence of first an axial and then a radial motion.

A pouring element is also known from the U.S. Pat. No. 5,141,133, in which the screw cap and cutting elements are manufactured as a single piece. This pouring element with its flange is attached from outside onto the composite package. In this case, the cylinder-shaped frame is provided with an inner thread at its upper section, wherein the screw cap is provided with a corresponding outer thread. On opening the screw cap, the cutting element located in axial orientated grooves in the frame element is pushed downwards through the package material, wherein the package is opened.

Proceeding beyond this, the present invention has the object to develop and further improve the pouring element for cardboard/plastic packages mentioned initially and further described above, so that a simple construction with the retention of a simple three-component structure, an especially simple assembly and a good durability of the pre-assembled pouring element are achieved. In addition, a satisfactory penetration of the foil that is stretched across the pouring opening should be attained on first opening the unit. In addition, it is desirable if the cutting element is effectively prevented from falling into the interior of the package following the opening procedure.

The object is achieved in that the outer thread of the cutting element comprises two thread sections each having two thread lines each of which stretches along at least a quarter of the length of the cutting element and have an upward slope that is steeper than the inner thread of the screw cap, in that the inner thread of the frame element comprises two thread sections each of which stretches along about one half of the length and have an upward slope that corresponds to the upward slope of the outer thread of the cutting element, in that the frame element has an encompassing lip on its inner perimeter and that is directed downwards, and in that the cutting element is provided with a continuous groove in the region of its outer thread and which is parallel to the lip and which is suitable for reception of the lip with the cutting element projecting from the frame element.

The present invention has established that in the above manner the cutting element is always found to be in a precise position. Following the removal from the injection moulding equipment, a number of peripherally distributed, radially orientated connecting bridges are provided for establishing joints between the frame element and the cutting element, which pass between the underside of the cutting element and upper edge of the frame element, and which only become disturbed on mutual penetration. Subsequently, dropping out of the cutting element from the downward opening frame element during transportation or its attachment onto the composite package is reliably prevented. Even earlier on with the attachment of the pouring element onto the composite package, no damage of the PE-layer of the coated pouring element, that is situated below this element, can result since the cutting element of the actual cutting mechanism is protectively situated on the inner surface of the frame element.

In addition, the simultaneous axial mutual penetration of the screw cap unit comprising the cutting element and the frame element is sufficient to facilitate the end assembly of the pouring element that is to be applied onto a composite package.

Finally, dropping down of the cutting element into the interior of the package after its opening, and after screwing in of the cutting element situated on the lower inner edge of the frame element, is effectively prevented by the lip that is situated in the groove of the outer thread that is provided for it, and which in this way, ensures a positive-fit stop. The formation of a lip is useful from the point of view of construction technology, for the formation of the structural components, the frame element/cutting element, and, in addition, the lip also serves as buffer for the cutting element that is twisted into the frame element during the opening procedure.

By means of the steep slope of the thread on the cutting element, during the unscrewing of the screw cap, the cutting element very quickly moves with a cutting twist motion (overlying twisting and axial motion) into the over-layered moulded opening, so that foil that is present there is effectively disturbed and forced into the inside of the package without completely tearing it off, since the cutting element does not undertake a complete revolution.

According to another preferred form of the invention, the outer thread of the frame element is provided with a lower edge that is parallel in cross-section to an attachment flange and with an inclined upper edge, and which works together with the inner thread in the screw cap. For a simpler (axial) application of the screw cap, it can be advantageous, in a preferred arrangement of the invention, if the outer thread consists of a multiplicity of individual thread sections that are separated from one another by short spaces.

A further concept of the present invention discloses that the cutting element is provided with a number of encircling, radially arranged and outwardly directed projections, that operate together with corresponding inner lugs on the frame element to prevent unscrewing of the cutting element out of the frame element. They permit the turning of the cutting element to be undertaken in only one direction, in that they only allow for turning in a clockwise direction. These projections can either be formed from lugs that project radially from the outer side of the cutting element and/or from each of the horizontal extensions of the upper ends of the thread sections. It is especially preferred if the lugs and thread sections pass into each other.

Another advantageous form of the present invention provides for the cutting element in the area between the thread sections to have at least one break. This type of break acts as a “pouring window” and provides for the residual emptying, when the unit is stood upside down, and when the cutting element penetrates as a tube into the inside of the package, so that the product that is to be drained can flow out, and so that the package can be completely emptied.

According to another additional form of the present invention, the cutting element is provided on its outer side with a number of encircling, separately arranged and radially projecting lugs, which extend from the upper edge of the cutting element downwards and have a form that corresponds to the above-described lugs of the cutting element. Preferably, the lower ends of all lugs lie on a common surface that extends perpendicularly to the vertical axis of the cutting element, and which serve as secure reinforcement on the edge of the inner end of the frame element.

In accordance with a further preferred form of the present invention, the screw cap is provided with at least one internally situated pressure-transfer element which, during the initial twisting of the screw cap, activates the movement of the cutting element over the projecting lugs situated on the inside of the cutting element. This type of pressure transfer element is preferably trapeze-shaped and bent concentrically to the screw cap, and facilitates the situation of the screw cap during the assembly procedure in respect of the cutting element.

A pouring element, as produced in accordance with the process of the present invention, preferably is provided with a seal denoting its originality. This can be formed out of a flat, single component that is injection moulded in unitary manner with the screw cap and projecting radially from it, and is firmly attached to the flange on the frame element, so that the element is connected to the screw cap with at least one material bridge capable of being severed.

In addition, in the assembly procedure of the screw cap that is provided with an originality seal, the arrangement in respect of the frame element is simplified. There are, however, other procedures that are known per se, for the production of originality fasteners such, for example, as one that comprises a strap that surrounds the screw cap or similar component (see, WO 2004/000667 A1 designated as the guarantee band 25′).

The present invention is more closely illustrated by means of the following in a solely preferred example of a representative drawing of the production assembly. The drawings show:

FIG. 1 a vertical section of a re-closable pouring element before the assembly,

FIG. 2A a perspective view of a frame element and a single component, injection moulded cutting element prior to its assembly,

FIG. 2B the frame element with cutting element in side view in the direction of the arrow II in the FIG. 2A,

FIG. 3 a vertical section through the pouring element of the present invention as shown in FIGS. 2A and 2B, during the assembly, in which the screw cap is already reaching towards the cutting element,

FIG. 4 a vertical section of the finished assembly and axially compressed pouring element,

FIG. 5 a perspective view of the finished assembly and axially compressed pouring element,

FIG. 6 a perspective view of the cutting element pushed into the frame element prior to the opening procedure,

FIG. 7 a perspective representative section of the cutting element pushed into the frame element during the opening procedure,

FIG. 8 a perspective representative section of the cutting element pushed into the frame element after the opening procedure, and

FIG. 9 a perspective representative section of the cutting element pushed into the frame element after the opening procedure.

A preferred process for producing a pouring element is represented in the figures in order clearly to demonstrate the stages of the process of the present invention and to illustrate clearly the method of operation during the opening procedure. Thus, a pouring element produced in accordance with the present invention is represented in longitudinal section, and comprises a frame element 1, a one-piece, injection moulded cutting element 2 and a screw cap 3. The frame element 1 is provided with an outer thread 4 on its cylinder-shaped main body, and an encompassing flange 5 for connection onto a composite package (not shown). The outer thread 4 has a running lower edge 4B (shown in transverse section) that is parallel to the fastening flange 5 and a slanting upper edge 4T, for facilitating the exertion of a slight positive pressure during assembly of the screw cap 3.

On the inside of the frame element 1 there are two thread sections 6A and 6B. For greater understanding, in FIG. 2A the construction unit comprising the frame element 1 and the cutting element 2, is presented in perspective view, and in FIG. 2B in side aspect. There, the thread sections 7A, 7A′ and 7B, 7B′ that correspond to the thread sections 6A and 6B of an outer thread 7 of the cutting element 2, are discernible, wherein all the thread sections 6A, 6B and 7A, 7A′, 7B, 7B′ have the same steeper slope as that of the outer thread 7 of the frame element 1.

FIG. 1 also demonstrates that the frame element 1 has an encircling lip 8 on its lower, inner end, the function of which will be clarified later.

In addition, an inwardly projecting lug 9 can be seen on the upper edge of the frame element 1, which acts as a guide or buffer for the cutting element 2, which it will be further described later.

According to the present invention, the thread sections 7A, 7A′ and 7B, 7B′ have a groove 10 that runs parallel to the lip 8 which is suitable for accommodating the lip 8 while the cutting element 2 projects out from the frame element 1 (moulded position). This horizontal groove 10 is especially, readily recognisable from the FIG. 2B.

FIG. 2A also shows that the cutting element 2 has a number of lugs 11 and 12, on its upper region, of which only the front pair are discernible. In the preferred version of the invention, they are each integrally connected to a horizontal extension 7D of the thread section 7B. A horizontal extension 7C can also be seen on the opposite side of the thread section 7A. If desired, the lugs 12 and the extensions 7C and 7D can be dispensed with.

The section presented in FIG. 1 also clearly shows the peripherally arranged teeth 13 of the cutting element 2. These teeth 13, in the example of the preferred version, have sharply formed edges. In the upper, internal region of the cutting element 2, on the other hand, projecting lugs 14 and 14′ that are directed radially inwards, can be discerned, and this is especially obvious in FIG. 2A. The frame element 1 is connected to the cutting element 2 by means of a number of connecting bridges 15, and this is also apparent in FIG. 2.

The screw cap 3 is provided with an inner thread 16 that corresponds to the slope of the outer thread 4 of the frame element, and a pressure transferring element 17 that is situated along the inside and is substantially trapeze-shaped and concentric in relation to the screw cap. The pressure transferring element 17 acts on the cutting element 2 with the help of the lugs 14 and 14′ that project inwards during the initial opening of the pouring element, so that it is twisted along the length of the thread sections 6 and 7 and thus is screwed into the package interior.

For assembly of the pouring element of the present invention, the screw cap 3 is first moved over the cutting element 2 that projects out from the frame element 1, as is illustrated in FIG. 3. The other indicators in FIG. 3 refer to the same ones noted in the FIGS. 1 and 2 or 2B.

FIG. 4 demonstrates the completely assembled pouring element in vertical section, in which the axial movement of the placed screw cap 3 also causes the cutting element 2 to penetrate axially into the interior of the frame element 1, without itself rotating. It can be discerned that the tips of the teeth 13 are also situated at a distance from the frame element 1.

Owing to the special construction of the pressure transfer element 17, the precise positioning and arrangement of both the construction parts can be dispensed with. By means of axial compression the connecting bridges 15 are broken and the cutting element 2 is pushed into the frame element, wherein, simultaneously, the screw cap 3 is impacted against the frame element 1 so that the outer thread 4 of the frame element 1 is made to lie against the inner thread 16 of the screw cap 3. In order to simplify the assembly, the outer thread 4 is provided with a slanting upper flank 4T and is provided with its lower flank 4B in a horizontal position. In this way, with the axially directed compression, the thread 16 can more readily be pushed across the sloping flank 4T.

FIG. 5 illustrates the finished assembly of the pouring element, for a better overview it is again shown in perspective view. From this it is discernible that the pouring element of the invention also is provided with an originality seal; for this a plate 18 is injection moulded as a unit with the screw cap, which is situated in relation to the screw cap 3 over the connecting bridges 19, as can be clearly seen in FIG. 5. The plate 18 is provided, in the present case, with two pins 20 which penetrate corresponding depressions 21 (FIG. 2A) in the flange 5 on the frame element 1, and provide firm connection by means of caulking from below.

Finally, FIGS. 6 to 9 describe the functioning of the pouring element according to the present invention, during the initial opening procedure of the screw cap 3, which, for a better overview, is, however, not illustrated. Then, FIG. 6 illustrates the assembly arrangement of the FIGS. 4 and 5. From this it is apparent that the internally situated lugs 9 work together with the outer lugs 11 and to the end of the unified extensions 7C and 7D of the thread sections 7A and 7B connected to the lugs 11. The withdrawal twisting of the cutting element 2 from the frame element 1 in an upwards direction is effectively prevented by means of this buffering, since the cutting element 2 can only be rotated by unscrewing of the screw cap 3 in an anti-clockwise direction.

FIG. 7 illustrates the situation in which the teeth just connect with the foil that is to be penetrated (not shown). The axial pressure is thus transferred across the pressure transferring element 17 (not shown) onto the lugs 14 and 14′.

The FIGS. 8 and 9 illustrate the cutting element 2 in its final position, in which it remains available for further use of the screw cap with a repeat of the left- or right twisting and, in this way, reliably prevents the opened foil from entering the pouring canal. It is clear from this that both the lugs 12 (FIG. 8) as well as the lugs 11 (FIG. 9) make contact at their lower edges with the lip 8 and, in this way, fix the cutting element 2. The same applies to the lugs 12 (not demonstrated here). In addition, the groove 10 and all the lugs 11 and 12, that all lie diametrically opposite, are concerned with the task of ensuring that a “collapsing” of the cutting element 2 into the package interior is effectively prevented. 

1. A re-closable pouring element for cardboard/plastic composite packages, especially for drinks packages, comprising: an encompassing fixing flange; a frame element having an outer thread and an inner thread; a cutting element that has an outer thread; and a screw cap having an inner thread; wherein the cutting element is produced in a spraying position at an end of the frame element opposite to the fixing flange and together with this has been injection moulded across at least one connecting bridge in a unitary manner, and wherein the cutting element is situated in the interior of the frame element at an assembly position of the pouring element, wherein the outer thread of the cutting element comprises two thread sections each having two thread lines each of which stretches along at least a quarter of the length of the cutting element and have an upward slope that is steeper than the inner thread of the screw cap, wherein the inner thread of the frame element comprises two thread sections each of which stretches along about one half of the length and have an upward slope that corresponds to the upward slope of the outer thread of the cutting element, wherein the frame element has an encompassing lip on its inner perimeter and is directed downwards, and wherein the cutting element is provided with a continuous groove in the region of its outer thread that is parallel to the lip and is adapted for reception of the lip with the cutting element projecting from the frame element.
 2. The pouring element according to claim 1, wherein the outer thread of the frame element is provided with a lower edge that in cross section is parallel to the fixing flange and with a slanting upper edge and that operates in conjunction with the inner thread in the screw cap.
 3. The pouring element according to claim 1, wherein the outer thread comprises a number of individual thread sections.
 4. The pouring element according to claim 1, wherein the cutting element is provided with a number of encompassing, radially orientated and outwardly directed projections which work together with corresponding inner lugs on the frame element and thereby prevent a reverse turning of the cutting element out of the frame element.
 5. The pouring element according to claim 4, wherein the projections situated on the outside of the cutting element comprise radially orientated lugs.
 6. The pouring element according to claim 4, wherein the projections are formed from each of the horizontal extensions of the upper ends of the thread sections of the cutting element.
 7. The pouring element according to claim 5, wherein the lugs and the thread sections of the cutting element enter in one another.
 8. The pouring element according to claim 1, wherein the cutting element is provided with at least one separation in the region between the thread sections of the cutting element.
 9. The pouring element according to claim 1, wherein the cutting element is provided with a number of encompassing, separately arranged and radially projecting lugs on its outer side, the lugs are directed from the upper edge of the cutting element downwards and are formed from each of the horizontal extensions of the upper ends of the thread sections.
 10. The pouring element according to claim 5, wherein the lower ends of the lugs are disposed together along a surface perpendicular to a vertical axis of the cutting element in order to provide support on the lip for the cutting element as it extends out of the frame element.
 11. The pouring element according to claim 9, wherein the lower ends of the lugs are disposed together along a surface perpendicular to a vertical axis of the cutting element in order to provide support on the lip for the cutting element as it extends out of the frame element.
 12. The pouring element according to claim 1, wherein the screw cap is provided with at least one internally placed pressure-transferring element and the cutting element has a number of lugs on the inside of the cutting element, wherein the initial twisting open of the screw cap over the lugs on the inside of the cutting element brings about the movement of the cutting element.
 13. The pouring element according to claim 1, wherein at least one of the pressure transferring elements is substantially trapezoidally shaped and orientated in a concentric manner to the screw cap.
 14. The pouring element according to claim 1, wherein the pouring element is provided with an originality seal.
 15. The pouring element according to claim 14, wherein a flat plate injection moulded in a unitary manner together with the screw cap and projecting radially from the screw cap serves as the originality seal, wherein the originality seal is firmly attached to the flange on the frame element prior to the final assembly of the pouring element. 